Interactions between mitral valve and left ventricle analysed by 2D speckle tracking in patients with mitral valve prolapse: one more piece to the puzzle.

Abstract

Two-dimensional echocardiography often reveals abnormal left ventricle (LV) lateral wall kinetics in patients presenting with mitral valve prolapse (MVP). However, relations between MVP and LV deformation are not clearly established. The aim of this study was to assess and quantify mitral valve chordae, leaflets, and LV myocardial interactions using speckle tracking echocardiography (STE). Using STE-derived longitudinal strain curves, LV peak longitudinal strain (PLS, %), post-systolic index (PSI), and pre-stretch index (PST) were analysed in 100 patients with MVP and normal LV ejection fraction. Global, regional, and segmental values were compared according to mitral regurgitation severity and MVP location. Twenty healthy subjects served as control patients. There was no significant difference among control and MVP group for global and regional PLS (-23.7 ± 3.2 vs. -23.1 ± 2.2). In contrast, patients with MVP had significantly higher values of global PST (3.2 ± 4.1 vs. 1.3 ± 1.2; P = 0.01) and global PSI (3.2 ± 0.4 vs. 1.7 ± 1.1; P = 0.05) compared with controls, located mainly in the lateral wall and basal segments. Both anterior and posterior MVPs were responsible for PSI in basal inferior segments and PST in anterior ones. Mid-wall segmental deformation pattern changes were mainly observed at the level of the segments adjacent to the papillary muscle. This study supports the hypothesis that pathological early-systolic shortening and late systolic, post-systolic deformation are attributed to an increased interaction between wall deformation and mitral valve events in patients with MVP. STE is a useful tool in the assessment of interplays between MV leaflets and myocardium and helps to demonstrate changes in temporal pattern of myocardial deformation.